United States Patent Application Publication No. U.S. 2002/0147061 A1 published Oct. 10, 2002 on an Athlete Training Device invented by myself and Jeffrey Lowery discloses a multiple dummy sled with the dummies positioned about an arc and facing toward the center of the arc. The dummies are spring loaded and are adjustable in height.
A blocking sled with two spring biased dummies is shown in U.S. Pat. No. 3,216,724 issued Nov. 9, 1965 to R. O. Williams for a Football Practice Apparatus.
U.S. Pat. No. 5,383,523 issued Jan. 31, 1995 to C. P. Forrest for a Dual Motion Blocking Sled shows a dummy mounted on a spring biased arm which slides upwardly and rearwardly in a support when an athlete strikes the dummy. The dummy may be lifted upwardly as allowed by a parallel linkage and a multiple position pin which may be positioned to limit up or down swinging movement of the parallel linkage.
U.S. Pat. No. 3,326,553 issued Jun. 20, 1967 to C. P. Forrest for a Multi-Purpose Wheeled Football Training Apparatus shows a tricycle type vehicle with a pair of blocking pads. The rear wheels may be braked simultaneously or individually.
U.S. Pat. No. 4,087,89 issued to C. P. Forrest on May 2, 1978 for a Football Lineman Trainer discloses a multiple dummy sled with retractable wheels at its front and rear. The sled is provided with a laterally shiftable dummy. A roller may be lowered to reduce the blocking force needed to move the sled.
Although a wide variety of football practice sleds have been used, and proposed for use, there is a need for a sled to train blockers which more closely simulates actual playing conditions and which helps to develop proper stance and blocking technique.